With the passing of years, many buildings are easily damaged under the continuous environmental deterioration. In order to prevent any tragedy happens due to collapse of building. Therefore, reinforcing buildings become a new direction and receive much attention in the industry.
The development of the reinforcement industry is also rapidly developing, and new reinforcement materials and methods are constantly emerging, and there are more and more methods for structural reinforcement.
Each structural reinforcement method can be divided into two categories: direct reinforcement and indirect reinforcement. Direct reinforcement includes increasing the cross-section reinforcement method, pasting fiber composite material reinforcement method, etc. Indirect reinforcement includes external prestressed reinforcement method, prestressed carbon fiber composite plate reinforcement method, etc.
The direct reinforcement method of bonding carbon fiber composite directly to the structures is efficient and has been widely used since 1980s due to low-cost.
Compared with traditional reinforcement methods, carbon fiber composite material reinforcement has many obvious advantages, such as:
1) Carbon fiber materials have a light weight and yet superior mechanical properties, high strength, and superior corrosion resistance. The buildings can be properly reinforced without damaging the integrity of the original structure.
2) The carbon fiber reinforcement construction method is convenient, cost-effective, and high in efficiency. The on-site construction does not require large mechanical equipment, and the repair time is short. It can also be constructed in narrow spaces.
3) Carbon fiber materials have formability and have great advantages for complex curved and anisotropic structures, such as tunnels.
4) Carbon fiber materials themselves have high corrosion resistance to acids, alkalis, and salts.
Carbon fiber reinforcement sounds like unbeatable but in many case, carbon fiber will not be adopted.
Let’s check it out!
Firstly, carbon fiber reinforcement can only be applied to definite materials that it cannot be used with plain concrete components, and it is also not applicable to the reinforcement of components with a longitudinal tensile reinforcement ratio of less than 0.2% on one side. Further on-site measurement is required before taking action to evaluate the strength which should be higher than C15 and the surface tensile bond strength of the concrete should not be lower than 1.5MPa.
Secondly, the strength and stress resistant level of the original structure have to be taken into account. Carbon fiber materials are soft and have low compressive strength. Therefore, they are suitable for the reinforcement of reinforced concrete components under bending, axial compression, large eccentric compression, and tension, such as beams and columns. For compressed structures, such as walls, the effect is minimal.
Thirdly, special protective measures are needed and tailor made adhesive agent is considered if the reinforced buildings are exposed to high temperatures, high humidity, erosion, and other factors for a long time. During construction, it is also necessary to pay attention to the need for specialized construction processes to follow standardized construction procedures.
Finally, adhesives play important role in reinforcing concrete structures with carbon fiber.
The impregnating adhesive used in carbon fiber materials has a strong bonding effect on concretebut not for steel and hence should be avoided.
The above four points tell us that the method of pasting fiber reinforcement cannot be applied on all situations. For different structural components, we should consider the characteristics of the original materials and choose the suitable method flexibly.
High Gain Industrial Limited has been striving in the composite materials industry for over 30 years. It is equipped with various production methids and facilities including autoclave, filament winding, autoclave, just to name a few. We provide total one stop solutions to customers, from product develop to mold design and production that aim at solving customers’ needs with sophisticated workmanship and concrete experience.
